The study of diseases in horses encompasses a wide range of conditions affecting equine health, including infectious diseases, metabolic disorders, and genetic abnormalities. These diseases can impact various systems within the horse, such as respiratory, gastrointestinal, and musculoskeletal systems, and can lead to significant health challenges. Research in this area focuses on understanding the pathophysiology, diagnosis, prevention, and treatment of equine diseases. Common diseases studied include equine influenza, equine herpesvirus, and laminitis. This page provides access to peer-reviewed research studies and scholarly articles that explore the etiology, clinical presentation, and management strategies of diseases in horses, contributing to the advancement of equine veterinary medicine.
Sheoran AS, Nally JE, Donahue JM, Smith BJ, Timoney JF.Leptospira-specific antibody isotypes in sera of late term equine fetuses aborted due to Leptospira interrogans serovar pomona-type kennewicki infection were characterized and compared with those of their dams. IgM was the dominant Leptospira-Specific isotype in both fetuses and mares. However, IgGa was the isotype in highest concentration in petal sera and strong Leptospira-specific IgGa but no IgGb and little or no IgG(T) were detected. In contrast, although IgGb was quantitatively the dominant isotype in mares serum, Leptospira-specific serum IgG in aborting mares was dominated by IgG(T) bu...
de Clercq T, Verschooten F, Ysebaert M.A collection of 69 isolated navicular bones, normal or affected with navicular disease, was examined radiographically using dorsopalmar, lateromedial and palmaroproximal-palmarodistal views. Radiographic findings on each view were recorded. A radiographic diagnosis of normality or navicular disease was made, first on each view separately and afterwards based on the combination of the 3 views. Forty-four navicular bones were considered radiographically normal and 25 navicular bones had distinct signs of radiographic navicular disease. The dorsopalmar and the lateromedial views of each navicular...
Hahn CN, Mayhew IG.The effect of an ocular administration of the alpha-1 adrenergic agonist phenylephrine was studied in 23 cases of grass sickness and 12 control horses. In the horses with grass sickness there was a significantly greater mean increase in the size of the palpebral fissure, as measured by the change in the angle of the eyelashes to the head observed from a frontal view.
MacLeay JM, Valberg SJ, Pagan JD, Xue JL, De La Corte FD, Roberts J.To determine the effects of 3 rations (low grain, fat, high grain) on plasma creatine kinase (CK) activity and lactate concentration in Thoroughbred horses with recurrent exertional rhabdomyolysis (RER). Methods: 5 Thoroughbreds with RER and 3 healthy Thoroughbreds (control horses). Methods: Rations were formulated to meet (low-grain and fat rations) or exceed (high-grain ration) daily energy requirements. Each ration was fed to horses in a crossover design for 3 weeks. Horses were exercised on a treadmill Monday through Friday; maximum speed on Monday and Friday was 11 m/s (6% slope), on Tues...
Yasuda R, Kawano J, Onda H, Takagi M, Shimizu A, Anzai T.To determine patterns of methicillin-resistant staphylococci isolated from apparently healthy horses. Methods: 44 horses from 8 riding clubs in Japan. Methods: Methicill in-resistant staphylococci were isolated from the skin or nares, using a selective medium containing a beta-(symboric) lactam antibiotic, ceftizoxime. Clonality of isolates was determined by use of pulsed-field gel electrophoresis. Detection of mecA, mecl, and mecR1 genes was accomplished by use of polymerase chain reactions. Results: Of the 44 horses, 13 (29.5%) yielded 15 isolates of methicillin-resistant staphylococci. The ...
Patterson-Kane JC, Tramontin RR, Giles RC, Harrison LR.A 14-year-old Thoroughbred gelding with a history of acute onset of hematuria was presented for necropsy. Transitional cell carcinoma of the urinary bladder with intra-abdominal dissemination was diagnosed. Tumor masses were observed on the splenic capsule and surrounding the distal abdominal aorta. Tumor cells showed diffuse cytoplasmic reactivity for cytokeratin but were negative for epithelial membrane antigen, carcinoembryonic antigen, tumor-associated glycoprotein 72, and vimentin.
Haechler S, Van den Ingh TS, Rogivue C, Ehrensperger F, Welle M.Congenital hepatic fibrosis with autosomal recessive or dominant inheritance has been described in humans, cats, piglets, and dogs. In horses, only two cases of congenital hepatic fibrosis have been previously reported. This retrospective study of records from the Institute for Animal Pathology, University of Berne, identified 30 foals with liver lesions compatible with congenital hepatic fibrosis. Anamnestic data revealed clinical signs of severe liver injury in most affected animals. Pathologic examination showed severely enlarged, firm livers with thin-walled cysts. Histologically, the live...
Guy JS, Breslin JJ, Breuhaus B, Vivrette S, Smith LG.A coronavirus was isolated from feces of a diarrheic foal and serially propagated in human rectal adenocarcinoma (HRT-18) cells. Antigenic and genomic characterizations of the virus (isolate NC99) were based on serological comparison with other avian and mammalian coronaviruses and sequence analysis of the nucleocapsid (N) protein gene. Indirect fluorescent-antibody assay procedures and virus neutralization assays demonstrated a close antigenic relationship with bovine coronavirus (BCV) and porcine hemagglutinating encephalomyelitis virus (mammalian group 2 coronaviruses). Using previously des...
Kablack KA, Embertson RM, Bernard WV, Bramlage LR, Hance S, Reimer JM, Barton MH.Historical, physical and diagnostic data were reviewed retrospectively in 31 equine neonates with uroperitoneum. Gender predilection was not observed, and classic electrolyte abnormalities were seen in less than 50% of the cases. Aetiologies for uroperitoneum have been well described, but this review found that septicaemia/severe illness played a crucial role the outcome of uroperitoneum. Approximately half the individuals with uroperitoneum had positive sepsis scores. Foals receiving fluid therapy were more likely to be septic and to have normal electrolyte concentrations. Ultrasonographic fi...
Suzuki Y, Ito T, Suzuki T, Holland RE, Chambers TM, Kiso M, Ishida H, Kawaoka Y.The distribution of sialic acid (SA) species varies among animal species, but the biological role of this variation is largely unknown. Influenza viruses differ in their ability to recognize SA-galactose (Gal) linkages, depending on the animal hosts from which they are isolated. For example, human viruses preferentially recognize SA linked to Gal by the alpha2,6(SAalpha2,6Gal) linkage, while equine viruses favor SAalpha2,3Gal. However, whether a difference in relative abundance of specific SA species (N-acetylneuraminic acid [NeuAc] and N-glycolylneuraminic acid [NeuGc]) among different animal...
Hinton TM, Li F, Crabb BS.Equine rhinitis A virus (ERAV) has recently been classified as an aphthovirus, a genus otherwise comprised of the different serotypes of Foot-and-mouth disease virus (FMDV). FMDV initiates translation via a type II internal ribosomal entry site (IRES) and utilizes two in-frame AUG codons to produce the leader proteinases Lab and Lb. Here we show that the ERAV 5' nontranslated region also possesses the core structures of a type II IRES. The functional activity of this region was characterized by transfection of bicistronic plasmids into BHK-21 cells. In this system the core type II structures, ...
Várady M, Königová A, Corba J.The present study included 19 stud farms, including 243 horses, that were investigated for the occurrence of anthelmintic resistant cyathostomes. The number of horses on the farms varied from nine to more than 100, and horses of all ages were included. A minimum of seven horses were used for faecal egg count reduction (FECR) tests. The anthelmintics included were: fenbendazole (paste formulation), ivermectin (paste formulation) and pyrantel (powder). Resistance to benzimidazoles was detected on 14 farms, with FECR values ranging from 65.1 to 86.3%. Larval cultures after fenbendazole treatment ...
Bureau F, Delhalle S, Bonizzi G, Fiévez L, Dogné S, Kirschvink N, Vanderplasschen A, Merville MP, Bours V, Lekeux P.In most cells trans-activating NF-kappaB induces many inflammatory proteins as well as its own inhibitor, IkappaB-alpha, thus assuring a transient response upon stimulation. However, NF-kappaB-dependent inflammatory gene expression is persistent in asthmatic bronchi, even after allergen eviction. In the present report we used bronchial brushing samples (BBSs) from heaves-affected horses (a spontaneous model of asthma) to elucidate the mechanisms by which NF-kappaB activity is maintained in asthmatic airways. NF-kappaB activity was high in granulocytic and nongranulocytic BBS cells. However, NF...
Ceci L, Carelli G.This paper reviews basic information on the knowledge of tick-borne diseases, babesiosis, anaplasmosis and theileriosis, in horses, cattle, sheep and goats in Italy with particular reference to the southern part of the country. It is stressed that there is limited knowledge about the parasite species present, their vectors, distribution, prevalence and impact on livestock production and there is the need to assess their epidemiology. A study carried out in the Apulia region to assess the prevalence of Anaplasma marginale infection in 1,648 cattle showed a seroprevalence of 17% using the Card A...
Kosuge J, Goto Y, Shinjo T, Anzai T, Takatori K.Sixty-six new and used samples of horse bedding materials: 60 rice straws, 2 wheat straws, 2 timothy hays and 2 wood chips, were collected from horse breeding stables of 33 farms in Japan and examined for the presence of Emericella nidulans (E. nidulans; anam. Aspergillus nidulans). The incidence of E. nidulans in the bedding materials was 75.8% and there was no significant difference in detection of the fungus between the new and used materials (25 out of the 33 samples, respectively). The growth of E. nidulans isolated in sterilized rice straw culture was accelerated by the addition of water...
Losinger WC, Traub-Dargatz JL, Sampath RK, Morley PS.Of 7320 equine foals reported born alive during 1997 on 1043 operations that had equids on 1 January 1997, and that participated in the United States National Animal Health Monitoring System (NAHMS) Equine 1998 Study, 120 foals were reported to have died (by either euthanasia or natural causes) within the first 2 days of a live birth. The weighted estimate was 1.7% mortality (standard error=0.5) within the first 2 days of live birth for all foals born on operations in the 28 states included in the study.A multivariable logistic-regression model revealed that foals born in the southern region w...
Vaneechoutte M, Devriese LA, Dijkshoorn L, Lamote B, Deprez P, Verschraegen G, Haesebrouck F.Acinetobacter baumannii was isolated from tips clipped from seven intravenous jugular catheters collected from horses in the Ghent University equine clinic. They originated from seven different horses. Three of the seven showed evidence of local infection.
Huxtable CR, de Lahunta A, Summers BA, Divers T.Marginal siderosis is recognized in humans as an uncommon clinicopathologic entity characterized by degeneration of neural tissue at the surface of the brain and spinal cord, in association with the accumulation of hemosiderin, and resulting from chronic subarachnoid hemorrhage. The sources of hemorrhage are various and include neoplasms, malformations, cysts, and vasculopathy. Marginal siderosis of the spinal cord due to a myxopapillary ependymoma was diagnosed in a 19-year-old Dutch Warm Blood horse with clinical signs of myelopathy. There is only one previous report of marginal siderosis in...
Don-van't Slot HP, van der Kolk JH.Severe-Combined-Immunodeficiency-Disease (SCID) is discussed with special reference to its pathogenesis, clinical symptoms, pathology, and diagnosis. The disorder has been observed in the USA, Canada, Great Britain, and Australia and is characterized by an autosomal recessive mode of inheritance. The clinical features of the disease seen in Arab foals under 46 days of age are intermittent fever, (adenoviral) pneumonia, and weight loss sometimes associated with diarrhoea. From 1998 on, the SCID gene can be detected in the Netherlands by means of DNA analysis.
van Loon G, Tavernier R, Duytschaever M, Fonteyne W, Deprez P, Jordaens L.A transvenous, screw-in electrode was implanted in the right atrium of a healthy pony and connected with an implantable pulse generator programmed to deliver bursts of electrical stimuli to the atrium. Initially, cessation of burst pacing resulted in short (less than 1 minute), self-terminating episodes of atrial fibrillation. As burst pacing continued, the episodes of induced atrial fibrillation became longer. After 3 weeks of continuous atrial pacing, atrial fibrillation became sustained (56 hours). This model of pacing induced atrial fibrillation can be used to study the mechanisms leading ...
Richards AJ, Kelly DF, Knottenbelt DC, Cheeseman MT, Dixon JB.This report summarises clinical and pathological observations on Fell pony foals with a range of signs that included ill thrift, anaemia, respiratory infection, glossal hyperkeratosis and diarrhoea. Some of the foals had normochromic, normocytic anaemia and some had low levels of plasma proteins, including immunoglobulin G. Antibiotic and supportive treatment was ineffective and all affected foals died or were killed on humane grounds. Postmortem examination of 12 foals and tissues from 2 other foals revealed a range of lesions that included glossal hyperkeratosis, typhlocolitis, intestinal cr...
Hodgin EC, Miller DA, Lozano F.Leptospira infection was diagnosed as the cause of 4 late-term equine abortions/stillbirths and 1 neonatal death in Louisiana. The most consistent gross and microscopic lesions were icterus and interstitial nephritis, respectively. Diagnoses were based on visualization of compatible spirochetes in Warthin-Starry-stained sections of kidney, liver, and placenta. Confirmation by immunofluorescence was made in 2 cases.
Orsini JA, Nunamaker DM, Jones CJ, Acland HM.A large oral squamous cell carcinoma in a 27-year-old Arabian stallion was removed by partial excision of the incisive bone. There was no gross evidence of recurrence or metastasis 5 months later.
Eckert J, Ossent P.A 14-year-old horse (imported to Switzerland from Ireland 8 years earlier) showed signs of chewing muscle atrophy. A severe chronic myositis, caused by numerous immature and mature female nematodes, was diagnosed in muscle samples obtained by biopsy and subsequently at necropsy. Most of the nematodes had invaded muscle fibres of the masseter, root of the tongue and anterior breast, only a few were found in the intermuscular interstitium. Isolated nematodes and parasite sections were clearly different from muscle larvae of Trichinella spp. but showed morphological similarities to Haycocknema pe...
Hinton M, Jones DR, Lewis IM, Thomson PE.A multiple clotting defect in a 3 month old Arab colt foal associated with a deficiency in Factors VIII, IX, and XI is described. No abnormalities in clotting factors were detected in the colt's sire, dam, half-sister and half-brother.
Pacyńska JA.Horses are characterized by a very high incidence of mycoses in comparison with most livestock and companion animals. They are highly susceptible to asymptomatic infections caused by yeast-like fungi, but the carrier state may be disrupted under the influence of autogenic and allogenic factors. The above leads to severe organ mycoses, often with an acute form of infection. "Carrier horses" may also act as vectors which transmit potential pathogens between individuals and species. The aim of this study was to identify yeast-like fungi and yeast colonizing the ontocenoses of healthy horses and t...
Parmar J, Winterbottom A, Cooke F, Lever AM, Gaunt M.Streptococcus equi is a common equine infectious disease, but transmission to man is rare and confined to those who commonly come into close contact with horses. Similarly, prosthetic stent graft infection is a rare complication of endovascular aortic aneurysm repair. We describe the first reported case of aortic stent graft with S. equi occurring in a professional racehorse trainer. Clinical presentation, investigations, imaging and management of this case are described. In conclusion, clinicians should consider infection with rare organisms in patients with prosthetic implants who regularly ...
Faehrmann P, Riddell K, Read AJ.We describe the clinical signs and disease course during an outbreak of equine influenza (EI) in naïve horses in a police stables in Sydney, New South Wales, Australia.
Crawley GR, Grant BD, Krpan MK, Major MD.Thirteen cases of partial limb amputation in horses were reviewed. Nine horses (69%) survived 18 to 111 months (mean, 41 months). Four unsuccessfully treated horses were euthanatized within 21 days of surgery. The horses' ages at amputation were 4 to 13 years (mean, 7.3 years). There was no predilection for the left or right limb nor for fore or hind limb involvement. Osteomyelitis in six horses (46%) was the most common cause for amputation. Severe, open, comminuted fractures of the third metacarpal bone that were impossible to stabilize by any currently available technique in four horses (31...
Mainar-Jaime RC, House JK, Smith BP, Hird DW, House AM, Kamiya DY.To predict mortality of horses by use of clinical data from the first day of hospitalization, to determine whether fecal shedding of Salmonella organisms is related to severity of clinical disease, and to determine the impact of fecal shedding of Salmonella organisms on mortality. Methods: Prospective study. Methods: 1,446 hospitalized horses. Methods: Medical information was obtained from horses hospitalized in an intensive care unit or isolation facility during a 4.5-year period. A model was created to predict mortality, using covariates determined on the day of admission. Predicted mortalit...
de Freitas CM, Leite RC, Lopes CM, Rodrigues DS, Paz GF, de Oliveira PR.Some reproductive parameters of adult stages of Amblyomma cajennense ticks were studied. The capacity of virgin females to reproduce by parthenogenesis was evaluated, during an experimental infestation, in absence of males, on a horse (Equus cabalus). Ticks were spread either completely free or in limited sites on the body of the animal. The engorged virgin females showed longer feeding periods and lighter body weights than those that had been fertilized. Some of these unmated females produced smaller egg masses, which had no embryonary development. On the other hand, females that had been ins...
Ruocco NA, Luedke LK, Fortier LA, Ducharme NG, Reesink HL.The most common pathologic manifestation of , a gram-positive, facultative intracellular bacterium, is pyogranulomatous pneumonia in foals and weanlings. Hematogenous spread of bacteria may subsequently occur, resulting in joint sepsis, osteomyelitis, or subcutaneous abscessation. Medical records from horses presenting to the Cornell University Equine Hospital from 1998 to 2018 were reviewed for cases diagnosed with joint and/or bone infection, and information about case progression and outcome were analyzed. We hypothesized that, despite advances in diagnostic imaging, antimicrobials and ant...
Sanders-Shamis M.Perirectal abscesses were diagnosed retrospectively in 6 horses treated for colic. The abscesses caused colic in the horses by producing an extraluminal obstruction that led to fecal impaction. The abscesses were diagnosed by rectal palpation and aspiration of exudate from the masses and were drained surgically. In horses in which the abscess involved abdominal organs, peritonitis developed.
Cuteri V, Takai S, Moscati L, Battistacci L, Pieramati C, Valente C.A serological survey of Rhodococcus equi infection was carried out on 602 blood samples collected from foals in central Italy. The assay was performed with an ELISA test using two different antigens prepared with reference strains of R. equi, ATCC 33071 and ATCC 6939. A positive reaction was obtained on 81 serum samples (13.45%) (OD > or = 0.3) using antigen ATCC 33071, and on 73 serum samples (12.12%) using antigen ATCC 6939. Although the frequency of the disease was not high, the serological positivity was about 13%. There was no statistically significant difference between males and fema...
Ikadai H, Kabamoto S, Xuan X, Igarashi I, Nagasawa H, Fujisaki K, Suzuki N, Mikami T.Babesia caballi merozoites were prepared by combining two improved methods of cultivation and purification of merozoites using Percoll-gradiation, and the protein compositions of merozoites were analyzed by two-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western blotting. The relative molecular masses of the major proteins and protein masses separated by electrophoresis were >94, 80-70, 50-45, 34-30, 30-28 and 18 kDa. By Western blotting, twelve proteins or protein groups were recognized by pooled sera from two horses experimentally infected with B. caballi. Among...
Okamoto M, Kamitani M, Tunoda N, Tagami M, Nagamine N, Kawata K, Itoh H, Kawasako K, Komine M, Akihara Y, Shimoyama Y, Miyasho T, Hirayama K....No abstract available
Yepez-Mulia L, Arriaga C, Viveros N, Adame A, Benitez E, Ortega-Pierres MG.In order to determine the presence of Trichinella infections in horses slaughtered at an abattoir in Mexico, 147 serum samples were examined by two immunoenzymatic methods. Specific antibodies were detected by ELISA in 7% of the serum samples at a dilution 1:400 and in 10% at lower dilutions (1:20, 1:40) using Trichinella spiralis muscle larvae (ML) excretory/secretory (E/S) products. Serum samples from four naturally infected horses (confirmed by direct methods) gave negative O.D. values in an ELISA at a 1:400 dilution and only two of them were positive at a 1:20 and 1:40 dilutions. Serum sam...
Van Loon G, Jordaens L, Muylle E, Nollet H, Sustronck B.A five-year-old warmblood mare with atrial fibrillation was treated with quinidine sulphate. The atrial rhythm changed to atrial flutter and, because there were toxic effects, the treatment was discontinued. Seven months after the occurrence of the atrial flutter, treatment with a rapid atrial pacing technique restored a normal sinus rhythm. One year after the pacing therapy the horse was still in sinus rhythm and had been brought back into training.